All patches and comments are welcome. Please squash your changes to logical
commits before using git-format-patch and git-send-email to
patches@git.madduck.net.
If you'd read over the Git project's submission guidelines and adhered to them,
I'd be especially grateful.
7 <!-- Include any especially major or disruptive changes here -->
11 <!-- Changes that affect Black's style -->
15 <!-- Changes to blackd -->
19 <!-- Changes to how Black can be configured -->
21 - Do not format `__pypackages__` directories by default (#2836)
22 - Add support for specifying stable version with `--required-version` (#2832).
23 - Avoid crashing when the user has no homedir (#2814)
27 <!-- Major changes to documentation and policies. Small docs changes
28 don't need a changelog entry. -->
32 <!-- For example, Docker, GitHub Actions, pre-commit, editors -->
36 <!-- Changes to Black's terminal output and error messages -->
40 <!-- Changes to how Black is packaged, such as dependency requirements -->
44 <!-- Changes to the parser or to version autodetection -->
48 <!-- Changes that improve Black's performance. -->
52 At long last, _Black_ is no longer a beta product! This is the first non-beta release
53 and the first release covered by our new
54 [stability policy](https://black.readthedocs.io/en/stable/the_black_code_style/index.html#stability-policy).
58 - **Remove Python 2 support** (#2740)
59 - Introduce the `--preview` flag (#2752)
63 - Deprecate `--experimental-string-processing` and move the functionality under
65 - For stubs, one blank line between class attributes and methods is now kept if there's
66 at least one pre-existing blank line (#2736)
67 - Black now normalizes string prefix order (#2297)
68 - Remove spaces around power operators if both operands are simple (#2726)
69 - Work around bug that causes unstable formatting in some cases in the presence of the
70 magic trailing comma (#2807)
71 - Use parentheses for attribute access on decimal float and int literals (#2799)
72 - Don't add whitespace for attribute access on hexadecimal, binary, octal, and complex
74 - Treat blank lines in stubs the same inside top-level `if` statements (#2820)
75 - Fix unstable formatting with semicolons and arithmetic expressions (#2817)
76 - Fix unstable formatting around magic trailing comma (#2572)
80 - Fix mapping cases that contain as-expressions, like `case {"key": 1 | 2 as password}`
82 - Fix cases that contain multiple top-level as-expressions, like `case 1 as a, 2 as b`
84 - Fix call patterns that contain as-expressions with keyword arguments, like
85 `case Foo(bar=baz as quux)` (#2749)
86 - Tuple unpacking on `return` and `yield` constructs now implies 3.8+ (#2700)
87 - Unparenthesized tuples on annotated assignments (e.g
88 `values: Tuple[int, ...] = 1, 2, 3`) now implies 3.8+ (#2708)
89 - Fix handling of standalone `match()` or `case()` when there is a trailing newline or a
90 comment inside of the parentheses. (#2760)
91 - `from __future__ import annotations` statement now implies Python 3.7+ (#2690)
95 - Speed-up the new backtracking parser about 4X in general (enabled when
96 `--target-version` is set to 3.10 and higher). (#2728)
97 - _Black_ is now compiled with [mypyc](https://github.com/mypyc/mypyc) for an overall 2x
98 speed-up. 64-bit Windows, MacOS, and Linux (not including musl) are supported. (#1009,
103 - Do not accept bare carriage return line endings in pyproject.toml (#2408)
104 - Add configuration option (`python-cell-magics`) to format cells with custom magics in
105 Jupyter Notebooks (#2744)
106 - Allow setting custom cache directory on all platforms with environment variable
107 `BLACK_CACHE_DIR` (#2739).
108 - Enable Python 3.10+ by default, without any extra need to specify
109 `--target-version=py310`. (#2758)
110 - Make passing `SRC` or `--code` mandatory and mutually exclusive (#2804)
114 - Improve error message for invalid regular expression (#2678)
115 - Improve error message when parsing fails during AST safety check by embedding the
116 underlying SyntaxError (#2693)
117 - No longer color diff headers white as it's unreadable in light themed terminals
119 - Text coloring added in the final statistics (#2712)
120 - Verbose mode also now describes how a project root was discovered and which paths will
121 be formatted. (#2526)
125 - All upper version bounds on dependencies have been removed (#2718)
126 - `typing-extensions` is no longer a required dependency in Python 3.10+ (#2772)
127 - Set `click` lower bound to `8.0.0` (#2791)
131 - Update GitHub action to support containerized runs (#2748)
135 - Change protocol in pip installation instructions to `https://` (#2761)
136 - Change HTML theme to Furo primarily for its responsive design and mobile support
138 - Deprecate the `black-primer` tool (#2809)
139 - Document Python support policy (#2819)
145 - Fix determination of f-string expression spans (#2654)
146 - Fix bad formatting of error messages about EOF in multi-line statements (#2343)
147 - Functions and classes in blocks now have more consistent surrounding spacing (#2472)
149 #### Jupyter Notebook support
151 - Cell magics are now only processed if they are known Python cell magics. Earlier, all
152 cell magics were tokenized, leading to possible indentation errors e.g. with
153 `%%writefile`. (#2630)
154 - Fix assignment to environment variables in Jupyter Notebooks (#2642)
156 #### Python 3.10 support
158 - Point users to using `--target-version py310` if we detect 3.10-only syntax (#2668)
159 - Fix `match` statements with open sequence subjects, like `match a, b:` or
160 `match a, *b:` (#2639) (#2659)
161 - Fix `match`/`case` statements that contain `match`/`case` soft keywords multiple
162 times, like `match re.match()` (#2661)
163 - Fix `case` statements with an inline body (#2665)
164 - Fix styling of starred expressions inside `match` subject (#2667)
165 - Fix parser error location on invalid syntax in a `match` statement (#2649)
166 - Fix Python 3.10 support on platforms without ProcessPoolExecutor (#2631)
167 - Improve parsing performance on code that uses `match` under `--target-version py310`
172 - Remove dependency on `regex` (#2644) (#2663)
178 - Bumped regex version minimum to 2021.4.4 to fix Pattern class usage (#2621)
184 - Warn about Python 2 deprecation in more cases by improving Python 2 only syntax
186 - Add experimental PyPy support (#2559)
187 - Add partial support for the match statement. As it's experimental, it's only enabled
188 when `--target-version py310` is explicitly specified (#2586)
189 - Add support for parenthesized with (#2586)
190 - Declare support for Python 3.10 for running Black (#2562)
194 - Fixed vim plugin with Python 3.10 by removing deprecated distutils import (#2610)
195 - The vim plugin now parses `skip_magic_trailing_comma` from pyproject.toml (#2613)
201 - Document stability policy, that will apply for non-beta releases (#2529)
202 - Add new `--workers` parameter (#2514)
203 - Fixed feature detection for positional-only arguments in lambdas (#2532)
204 - Bumped typed-ast version minimum to 1.4.3 for 3.10 compatibility (#2519)
205 - Fixed a Python 3.10 compatibility issue where the loop argument was still being passed
206 even though it has been removed (#2580)
207 - Deprecate Python 2 formatting support (#2523)
211 - Remove dependency on aiohttp-cors (#2500)
212 - Bump required aiohttp version to 3.7.4 (#2509)
216 - Add primer support for --projects (#2555)
217 - Print primer summary after individual failures (#2570)
221 - Allow to pass `target_version` in the vim plugin (#1319)
222 - Install build tools in docker file and use multi-stage build to keep the image size
229 - Fix missing modules in self-contained binaries (#2466)
230 - Fix missing toml extra used during installation (#2475)
236 - Add support for formatting Jupyter Notebook files (#2357)
237 - Move from `appdirs` dependency to `platformdirs` (#2375)
238 - Present a more user-friendly error if .gitignore is invalid (#2414)
239 - The failsafe for accidentally added backslashes in f-string expressions has been
240 hardened to handle more edge cases during quote normalization (#2437)
241 - Avoid changing a function return type annotation's type to a tuple by adding a
242 trailing comma (#2384)
243 - Parsing support has been added for unparenthesized walruses in set literals, set
244 comprehensions, and indices (#2447).
245 - Pin `setuptools-scm` build-time dependency version (#2457)
246 - Exclude typing-extensions version 3.10.0.1 due to it being broken on Python 3.10
251 - Replace sys.exit(-1) with raise ImportError as it plays more nicely with tools that
252 scan installed packages (#2440)
256 - The provided pre-commit hooks no longer specify `language_version` to avoid overriding
257 `default_language_version` (#2430)
263 - Configuration files using TOML features higher than spec v0.5.0 are now supported
265 - Add primer support and test for code piped into black via STDIN (#2315)
266 - Fix internal error when `FORCE_OPTIONAL_PARENTHESES` feature is enabled (#2332)
267 - Accept empty stdin (#2346)
268 - Provide a more useful error when parsing fails during AST safety checks (#2304)
272 - Add new `latest_release` tag automation to follow latest black release on docker
277 - The vim plugin now searches upwards from the directory containing the current buffer
278 instead of the current working directory for pyproject.toml. (#1871)
279 - The vim plugin now reads the correct string normalization option in pyproject.toml
281 - The vim plugin no longer crashes Black when there's boolean values in pyproject.toml
288 - Fix failure caused by `fmt: skip` and indentation (#2281)
289 - Account for += assignment when deciding whether to split string (#2312)
290 - Correct max string length calculation when there are string operators (#2292)
291 - Fixed option usage when using the `--code` flag (#2259)
292 - Do not call `uvloop.install()` when _Black_ is used as a library (#2303)
293 - Added `--required-version` option to require a specific version to be running (#2300)
294 - Fix incorrect custom breakpoint indices when string group contains fake f-strings
296 - Fix regression where `R` prefixes would be lowercased for docstrings (#2285)
297 - Fix handling of named escapes (`\N{...}`) when `--experimental-string-processing` is
302 - The official Black action now supports choosing what version to use, and supports the
303 major 3 OSes. (#1940)
309 - A space is no longer inserted into empty docstrings (#2249)
310 - Fix handling of .gitignore files containing non-ASCII characters on Windows (#2229)
311 - Respect `.gitignore` files in all levels, not only `root/.gitignore` file (apply
312 `.gitignore` rules like `git` does) (#2225)
313 - Restored compatibility with Click 8.0 on Python 3.6 when LANG=C used (#2227)
314 - Add extra uvloop install + import support if in python env (#2258)
315 - Fix --experimental-string-processing crash when matching parens are not found (#2283)
316 - Make sure to split lines that start with a string operator (#2286)
317 - Fix regular expression that black uses to identify f-expressions (#2287)
321 - Add a lower bound for the `aiohttp-cors` dependency. Only 0.4.0 or higher is
326 - Release self-contained x86_64 MacOS binaries as part of the GitHub release pipeline
328 - Always build binaries with the latest available Python (#2260)
332 - Add discussion of magic comments to FAQ page (#2272)
333 - `--experimental-string-processing` will be enabled by default in the future (#2273)
334 - Fix typos discovered by codespell (#2228)
335 - Fix Vim plugin installation instructions. (#2235)
336 - Add new Frequently Asked Questions page (#2247)
337 - Fix encoding + symlink issues preventing proper build on Windows (#2262)
343 - Refactor `src/black/__init__.py` into many files (#2206)
347 - Replaced all remaining references to the
348 [`master`](https://github.com/psf/black/tree/main) branch with the
349 [`main`](https://github.com/psf/black/tree/main) branch. Some additional changes in
350 the source code were also made. (#2210)
351 - Sigificantly reorganized the documentation to make much more sense. Check them out by
352 heading over to [the stable docs on RTD](https://black.readthedocs.io/en/stable/).
359 - Set `--pyi` mode if `--stdin-filename` ends in `.pyi` (#2169)
360 - Stop detecting target version as Python 3.9+ with pre-PEP-614 decorators that are
361 being called but with no arguments (#2182)
365 - Add `--no-diff` to black-primer to suppress formatting changes (#2187)
371 - Fix crash if the user configuration directory is inaccessible. (#2158)
374 [circumstances](https://github.com/psf/black/blob/master/docs/the_black_code_style.md#pragmatism)
375 in which _Black_ may change the AST (#2159)
377 - Allow `.gitignore` rules to be overridden by specifying `exclude` in `pyproject.toml`
378 or on the command line. (#2170)
382 - Install `primer.json` (used by `black-primer` by default) with black. (#2154)
388 - Fix crash on docstrings ending with "\\ ". (#2142)
390 - Fix crash when atypical whitespace is cleaned out of dostrings (#2120)
392 - Reflect the `--skip-magic-trailing-comma` and `--experimental-string-processing` flags
393 in the name of the cache file. Without this fix, changes in these flags would not take
394 effect if the cache had already been populated. (#2131)
396 - Don't remove necessary parentheses from assignment expression containing assert /
397 return statements. (#2143)
401 - Bump pathspec to >= 0.8.1 to solve invalid .gitignore exclusion handling
407 - Fixed a rare but annoying formatting instability created by the combination of
408 optional trailing commas inserted by `Black` and optional parentheses looking at
409 pre-existing "magic" trailing commas. This fixes issue #1629 and all of its many many
412 - `Black` now processes one-line docstrings by stripping leading and trailing spaces,
413 and adding a padding space when needed to break up """". (#1740)
415 - `Black` now cleans up leading non-breaking spaces in comments (#2092)
417 - `Black` now respects `--skip-string-normalization` when normalizing multiline
418 docstring quotes (#1637)
420 - `Black` no longer removes all empty lines between non-function code and decorators
421 when formatting typing stubs. Now `Black` enforces a single empty line. (#1646)
423 - `Black` no longer adds an incorrect space after a parenthesized assignment expression
424 in if/while statements (#1655)
426 - Added `--skip-magic-trailing-comma` / `-C` to avoid using trailing commas as a reason
427 to split lines (#1824)
429 - fixed a crash when PWD=/ on POSIX (#1631)
431 - fixed "I/O operation on closed file" when using --diff (#1664)
433 - Prevent coloured diff output being interleaved with multiple files (#1673)
435 - Added support for PEP 614 relaxed decorator syntax on python 3.9 (#1711)
437 - Added parsing support for unparenthesized tuples and yield expressions in annotated
440 - added `--extend-exclude` argument (PR #2005)
442 - speed up caching by avoiding pathlib (#1950)
444 - `--diff` correctly indicates when a file doesn't end in a newline (#1662)
446 - Added `--stdin-filename` argument to allow stdin to respect `--force-exclude` rules
449 - Lines ending with `fmt: skip` will now be not formatted (#1800)
451 - PR #2053: Black no longer relies on typed-ast for Python 3.8 and higher
453 - PR #2053: Python 2 support is now optional, install with
454 `python3 -m pip install black[python2]` to maintain support.
456 - Exclude `venv` directory by default (#1683)
458 - Fixed "Black produced code that is not equivalent to the source" when formatting
459 Python 2 docstrings (#2037)
463 - Self-contained native _Black_ binaries are now provided for releases via GitHub
470 - explicitly depend on Click 7.1.2 or newer as `Black` no longer works with versions
477 - re-implemented support for explicit trailing commas: now it works consistently within
478 any bracket pair, including nested structures (#1288 and duplicates)
480 - `Black` now reindents docstrings when reindenting code around it (#1053)
482 - `Black` now shows colored diffs (#1266)
484 - `Black` is now packaged using 'py3' tagged wheels (#1388)
486 - `Black` now supports Python 3.8 code, e.g. star expressions in return statements
489 - `Black` no longer normalizes capital R-string prefixes as those have a
490 community-accepted meaning (#1244)
492 - `Black` now uses exit code 2 when specified configuration file doesn't exit (#1361)
494 - `Black` now works on AWS Lambda (#1141)
496 - added `--force-exclude` argument (#1032)
498 - removed deprecated `--py36` option (#1236)
500 - fixed `--diff` output when EOF is encountered (#526)
502 - fixed `# fmt: off` handling around decorators (#560)
504 - fixed unstable formatting with some `# type: ignore` comments (#1113)
506 - fixed invalid removal on organizing brackets followed by indexing (#1575)
508 - introduced `black-primer`, a CI tool that allows us to run regression tests against
509 existing open source users of Black (#1402)
511 - introduced property-based fuzzing to our test suite based on Hypothesis and
512 Hypothersmith (#1566)
514 - implemented experimental and disabled by default long string rewrapping (#1132),
515 hidden under a `--experimental-string-processing` flag while it's being worked on;
516 this is an undocumented and unsupported feature, you lose Internet points for
517 depending on it (#1609)
521 - prefer virtualenv packages over global packages (#1383)
525 - added support for PEP 572 assignment expressions (#711)
527 - added support for PEP 570 positional-only arguments (#943)
529 - added support for async generators (#593)
531 - added support for pre-splitting collections by putting an explicit trailing comma
534 - added `black -c` as a way to format code passed from the command line (#761)
536 - --safe now works with Python 2 code (#840)
538 - fixed grammar selection for Python 2-specific code (#765)
540 - fixed feature detection for trailing commas in function definitions and call sites
543 - `# fmt: off`/`# fmt: on` comment pairs placed multiple times within the same block of
544 code now behave correctly (#1005)
546 - _Black_ no longer crashes on Windows machines with more than 61 cores (#838)
548 - _Black_ no longer crashes on standalone comments prepended with a backslash (#767)
550 - _Black_ no longer crashes on `from` ... `import` blocks with comments (#829)
552 - _Black_ no longer crashes on Python 3.7 on some platform configurations (#494)
554 - _Black_ no longer fails on comments in from-imports (#671)
556 - _Black_ no longer fails when the file starts with a backslash (#922)
558 - _Black_ no longer merges regular comments with type comments (#1027)
560 - _Black_ no longer splits long lines that contain type comments (#997)
562 - removed unnecessary parentheses around `yield` expressions (#834)
564 - added parentheses around long tuples in unpacking assignments (#832)
566 - added parentheses around complex powers when they are prefixed by a unary operator
569 - fixed bug that led _Black_ format some code with a line length target of 1 (#762)
571 - _Black_ no longer introduces quotes in f-string subexpressions on string boundaries
574 - if _Black_ puts parenthesis around a single expression, it moves comments to the
575 wrapped expression instead of after the brackets (#872)
577 - `blackd` now returns the version of _Black_ in the response headers (#1013)
579 - `blackd` can now output the diff of formats on source code when the `X-Diff` header is
584 - new option `--target-version` to control which Python versions _Black_-formatted code
587 - deprecated `--py36` (use `--target-version=py36` instead) (#724)
589 - _Black_ no longer normalizes numeric literals to include `_` separators (#696)
591 - long `del` statements are now split into multiple lines (#698)
593 - type comments are no longer mangled in function signatures
595 - improved performance of formatting deeply nested data structures (#509)
597 - _Black_ now properly formats multiple files in parallel on Windows (#632)
599 - _Black_ now creates cache files atomically which allows it to be used in parallel
600 pipelines (like `xargs -P8`) (#673)
602 - _Black_ now correctly indents comments in files that were previously formatted with
605 - `blackd` now supports CORS (#622)
609 - numeric literals are now formatted by _Black_ (#452, #461, #464, #469):
611 - numeric literals are normalized to include `_` separators on Python 3.6+ code
613 - added `--skip-numeric-underscore-normalization` to disable the above behavior and
614 leave numeric underscores as they were in the input
616 - code with `_` in numeric literals is recognized as Python 3.6+
618 - most letters in numeric literals are lowercased (e.g., in `1e10`, `0x01`)
620 - hexadecimal digits are always uppercased (e.g. `0xBADC0DE`)
622 - added `blackd`, see
623 [its documentation](https://github.com/psf/black/blob/18.9b0/README.md#blackd) for
626 - adjacent string literals are now correctly split into multiple lines (#463)
628 - trailing comma is now added to single imports that don't fit on a line (#250)
630 - cache is now populated when `--check` is successful for a file which speeds up
631 consecutive checks of properly formatted unmodified files (#448)
633 - whitespace at the beginning of the file is now removed (#399)
635 - fixed mangling [pweave](http://mpastell.com/pweave/) and
636 [Spyder IDE](https://www.spyder-ide.org/) special comments (#532)
638 - fixed unstable formatting when unpacking big tuples (#267)
640 - fixed parsing of `__future__` imports with renames (#389)
642 - fixed scope of `# fmt: off` when directly preceding `yield` and other nodes (#385)
644 - fixed formatting of lambda expressions with default arguments (#468)
646 - fixed `async for` statements: _Black_ no longer breaks them into separate lines (#372)
648 - note: the Vim plugin stopped registering `,=` as a default chord as it turned out to
653 - hotfix: don't freeze when multiple comments directly precede `# fmt: off` (#371)
657 - typing stub files (`.pyi`) now have blank lines added after constants (#340)
659 - `# fmt: off` and `# fmt: on` are now much more dependable:
661 - they now work also within bracket pairs (#329)
663 - they now correctly work across function/class boundaries (#335)
665 - they now work when an indentation block starts with empty lines or misaligned
668 - made Click not fail on invalid environments; note that Click is right but the
669 likelihood we'll need to access non-ASCII file paths when dealing with Python source
672 - fixed improper formatting of f-strings with quotes inside interpolated expressions
675 - fixed unnecessary slowdown when long list literals where found in a file
677 - fixed unnecessary slowdown on AST nodes with very many siblings
679 - fixed cannibalizing backslashes during string normalization
681 - fixed a crash due to symbolic links pointing outside of the project directory (#338)
685 - added `--config` (#65)
687 - added `-h` equivalent to `--help` (#316)
689 - fixed improper unmodified file caching when `-S` was used
691 - fixed extra space in string unpacking (#305)
693 - fixed formatting of empty triple quoted strings (#313)
695 - fixed unnecessary slowdown in comment placement calculation on lines without comments
699 - hotfix: don't output human-facing information on stdout (#299)
701 - hotfix: don't output cake emoji on non-zero return code (#300)
705 - added `--include` and `--exclude` (#270)
707 - added `--skip-string-normalization` (#118)
709 - added `--verbose` (#283)
711 - the header output in `--diff` now actually conforms to the unified diff spec
713 - fixed long trivial assignments being wrapped in unnecessary parentheses (#273)
715 - fixed unnecessary parentheses when a line contained multiline strings (#232)
717 - fixed stdin handling not working correctly if an old version of Click was used (#276)
719 - _Black_ now preserves line endings when formatting a file in place (#258)
723 - added `--pyi` (#249)
725 - added `--py36` (#249)
727 - Python grammar pickle caches are stored with the formatting caches, making _Black_
728 work in environments where site-packages is not user-writable (#192)
730 - _Black_ now enforces a PEP 257 empty line after a class-level docstring (and/or
731 fields) and the first method
733 - fixed invalid code produced when standalone comments were present in a trailer that
734 was omitted from line splitting on a large expression (#237)
736 - fixed optional parentheses being removed within `# fmt: off` sections (#224)
738 - fixed invalid code produced when stars in very long imports were incorrectly wrapped
739 in optional parentheses (#234)
741 - fixed unstable formatting when inline comments were moved around in a trailer that was
742 omitted from line splitting on a large expression (#238)
744 - fixed extra empty line between a class declaration and the first method if no class
745 docstring or fields are present (#219)
747 - fixed extra empty line between a function signature and an inner function or inner
752 - call chains are now formatted according to the
753 [fluent interfaces](https://en.wikipedia.org/wiki/Fluent_interface) style (#67)
755 - data structure literals (tuples, lists, dictionaries, and sets) are now also always
756 exploded like imports when they don't fit in a single line (#152)
758 - slices are now formatted according to PEP 8 (#178)
760 - parentheses are now also managed automatically on the right-hand side of assignments
761 and return statements (#140)
763 - math operators now use their respective priorities for delimiting multiline
766 - optional parentheses are now omitted on expressions that start or end with a bracket
767 and only contain a single operator (#177)
769 - empty parentheses in a class definition are now removed (#145, #180)
771 - string prefixes are now standardized to lowercase and `u` is removed on Python 3.6+
772 only code and Python 2.7+ code with the `unicode_literals` future import (#188, #198,
775 - typing stub files (`.pyi`) are now formatted in a style that is consistent with PEP
778 - progress when reformatting many files is now reported incrementally
780 - fixed trailers (content with brackets) being unnecessarily exploded into their own
781 lines after a dedented closing bracket (#119)
783 - fixed an invalid trailing comma sometimes left in imports (#185)
785 - fixed non-deterministic formatting when multiple pairs of removable parentheses were
788 - fixed multiline strings being unnecessarily wrapped in optional parentheses in long
791 - fixed not splitting long from-imports with only a single name
793 - fixed Python 3.6+ file discovery by also looking at function calls with unpacking.
794 This fixed non-deterministic formatting if trailing commas where used both in function
795 signatures with stars and function calls with stars but the former would be
796 reformatted to a single line.
798 - fixed crash on dealing with optional parentheses (#193)
800 - fixed "is", "is not", "in", and "not in" not considered operators for splitting
803 - fixed crash when dead symlinks where encountered
807 - don't populate the cache on `--check` (#175)
811 - added a "cache"; files already reformatted that haven't changed on disk won't be
812 reformatted again (#109)
814 - `--check` and `--diff` are no longer mutually exclusive (#149)
816 - generalized star expression handling, including double stars; this fixes
817 multiplication making expressions "unsafe" for trailing commas (#132)
819 - _Black_ no longer enforces putting empty lines behind control flow statements (#90)
821 - _Black_ now splits imports like "Mode 3 + trailing comma" of isort (#127)
823 - fixed comment indentation when a standalone comment closes a block (#16, #32)
825 - fixed standalone comments receiving extra empty lines if immediately preceding a
826 class, def, or decorator (#56, #154)
828 - fixed `--diff` not showing entire path (#130)
830 - fixed parsing of complex expressions after star and double stars in function calls
833 - fixed invalid splitting on comma in lambda arguments (#133)
835 - fixed missing splits of ternary expressions (#141)
839 - fixed parsing of unaligned standalone comments (#99, #112)
841 - fixed placement of dictionary unpacking inside dictionary literals (#111)
843 - Vim plugin now works on Windows, too
845 - fixed unstable formatting when encountering unnecessarily escaped quotes in a string
850 - added `--quiet` (#78)
852 - added automatic parentheses management (#4)
854 - added [pre-commit](https://pre-commit.com) integration (#103, #104)
856 - fixed reporting on `--check` with multiple files (#101, #102)
858 - fixed removing backslash escapes from raw strings (#100, #105)
862 - added `--diff` (#87)
864 - add line breaks before all delimiters, except in cases like commas, to better comply
867 - standardize string literals to use double quotes (almost) everywhere (#75)
869 - fixed handling of standalone comments within nested bracketed expressions; _Black_
870 will no longer produce super long lines or put all standalone comments at the end of
873 - fixed 18.3a4 regression: don't crash and burn on empty lines with trailing whitespace
876 - fixed 18.3a4 regression: `# yapf: disable` usage as trailing comment would cause
877 _Black_ to not emit the rest of the file (#95)
879 - when CTRL+C is pressed while formatting many files, _Black_ no longer freaks out with
880 a flurry of asyncio-related exceptions
882 - only allow up to two empty lines on module level and only single empty lines within
887 - `# fmt: off` and `# fmt: on` are implemented (#5)
889 - automatic detection of deprecated Python 2 forms of print statements and exec
890 statements in the formatted file (#49)
892 - use proper spaces for complex expressions in default values of typed function
895 - only return exit code 1 when --check is used (#50)
897 - don't remove single trailing commas from square bracket indexing (#59)
899 - don't omit whitespace if the previous factor leaf wasn't a math operator (#55)
901 - omit extra space in kwarg unpacking if it's the first argument (#46)
903 - omit extra space in
904 [Sphinx auto-attribute comments](http://www.sphinx-doc.org/en/stable/ext/autodoc.html#directive-autoattribute)
909 - don't remove single empty lines outside of bracketed expressions (#19)
911 - added ability to pipe formatting from stdin to stdin (#25)
913 - restored ability to format code with legacy usage of `async` as a name (#20, #42)
915 - even better handling of numpy-style array indexing (#33, again)
919 - changed positioning of binary operators to occur at beginning of lines instead of at
921 [a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b)
924 - ignore empty bracket pairs while splitting. This avoids very weirdly looking
925 formattings (#34, #35)
927 - remove a trailing comma if there is a single argument to a call
929 - if top level functions were separated by a comment, don't put four empty lines after
932 - fixed unstable formatting of newlines with imports
934 - fixed unintentional folding of post scriptum standalone comments into last statement
935 if it was a simple statement (#18, #28)
937 - fixed missing space in numpy-style array indexing (#33)
939 - fixed spurious space after star-based unary expressions (#31)
945 - only put trailing commas in function signatures and calls if it's safe to do so. If
946 the file is Python 3.6+ it's always safe, otherwise only safe if there are no `*args`
947 or `**kwargs` used in the signature or call. (#8)
949 - fixed invalid spacing of dots in relative imports (#6, #13)
951 - fixed invalid splitting after comma on unpacked variables in for-loops (#23)
953 - fixed spurious space in parenthesized set expressions (#7)
955 - fixed spurious space after opening parentheses and in default arguments (#14, #17)
957 - fixed spurious space after unary operators when the operand was a complex expression
962 - first published version, Happy 🍰 Day 2018!
966 - date-versioned (see: <https://calver.org/>)